Polk Township Vol. Fire Dept.

Ammonia - Farm Safety Info

With the Fall harvest season in full swing, many farmers must now turn their attention to replenishing their soil base with the application of ammonia. We have all seen the large white pressurized nurse tanks traveling down the highways and local roads.

What is Ammonia?

Ammonia (NH3) which is a chemical compound containing nitrogen and hydrogen. At atmospheric temperature and pressure, ammonia is a colorless gas with a very sharp characteristic odor. This gas can be liquefied by cooling or applying pressure. In appearance liquid anhydrous ammonia resembles water. The boiling point at atmospheric pressure is -28 degrees F. Above 900 degrees F, ammonia begins to decompose, reverting to hydrogen and nitrogen. At -107.9 degrees F, anhydrous ammonia freezes to form white crystals.

Is Ammonia Flammable?

Yes, ammonia will burn, but only if ammonia gas is mixed with the proper proportion of air. The flammable limits of a mixture are reported as 16-25 percent of ammonia vapor in air. Ammonia-air mixtures are difficult to ignite. It requires an intense ignition source and a high concentration of gas. The ignition temperature is in excess of 1560 degrees F.

But never let the flammable limits and high ignition temperatures give you a false level of security. It is impossible to test mixture percentages in a storage tank, nurse tank, applicator or piping. Under no condition should welding or cutting be done on ammonia equipment until the equipment has been completely decontaminated and thoroughly cleaned of all salt and ammonia.

What are Ammonia's affects on the human body?

Ammonia is not a poison. It has no cumulative toxic effect like lead or mercury. But it does have a very powerful corrosive affect on human tissue.

Exposure to atmospheric concentrations of ammonia above 5000 PPM of air (0.5 percent by volume) will cause death by suffocation within minutes.

Atmospheric concentrations above 2000 PPM (0.2 percent) will burn and blister the skin after a few seconds of exposure. Liquid ammonia in contact with the skin will produce severe burns not only by it's strong corrosive action, but also through the freezing effect produced by it's rapid evaporation.

Concentrations above 700 PPM (0.07 percent) will cause severe eye irritation, hemorrhages and swollen lids, and if not treated immediately may lead to partial or total loss of sight. Prolonged exposure at this level can lead to sever scarring of exposed eye tissue.

The tissue lining of the mouth, throat, nose and lungs is particularly sensitive to ammonia. Ammonia violently attacks the tissue of the lungs and upper respiratory tract. Exposure to concentrations above 1700 PPM (0.17 percent) may produce serious lung damage and unless properly treated, death will result.

O.S.H.A. has established the maximum allowable concentration of 50 PPM of NH3.

What to do if you are exposed

Inhalation: Remove the victim, at once, to an uncontaminated atmosphere. If breathing has ceased, immediately give artificial respiration. Call 911 for EMS and Fire Department response.

Skin Contact: Remove all contaminated clothing at once. Wash all affected areas thoroughly with large quantities of cool water, water and more water. Use whatever water sources are available like a livestock tank to submerse the victim. Call 911 for EMS and Fire department response.

Eye Contact: If small amounts of ammonia enter the eyes, they should be immediately irrigated with water for a minimum of 15 minutes. The eyelids should be held apart during the irrigation to insure water contact with all tissues of the eyes and lids. Call 911 for EMS and Fire department response.

Important Issues: Never wear contact lenses when working with ammonia. Be sure that the EMS and Fire department know that the injury and condition was caused by anhydrous ammonia.

Guidelines to follow

Basic Safety: Always have clean water available on all nurse tanks, applicators and at the main filling areas. Keep protective clothing and respirators nearby. Immediately flush any area of your body exposed to ammonia. Continue to immerse or rinse in clean water for at least 15 minutes.

Protective Gear: Always have rubber gloves, goggles and a face mask available. Use the goggles and gloves during transfer operation and while connecting, bleeding and disconnecting equipment.

No overfill: Never fill any tank beyond 85% of its liquid capacity.

Stay clear: Remain clear of valve and hose openings in case a valve is inadvertently opened. Stand upwind of transfer operations to stay out of ammonia vapors. Do not place your head or other part of your body in line with a valve opening.

Hauling: Be sure connections on trailers are in good condition and firmly secured to the pulling vehicle. Use safety chains.

Speed: When hauling nurse tank, don't exceed 35 MPH.

And for an exposure remember: Water, Water and more Water!

Remember, ammonia can be handled safely if all safety procedures are followed. Take the time to do it right - there may be no time to do it over! A few minutes of safety will prevent several months of treatment.

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John D. Einhorn
Sources: Daseke Ins.